Silica Dispersion Process for Polyurethane Reinforcement
Solution Overview
Problem
Current methods for producing silica-comprising dispersions with nanoparticles for polyurethane materials are costly and inefficient, as they require expensive precursors and result in large particle sizes, making it difficult to achieve effective reinforcement and handling of nanoscale fillers.
Innovation Solution
A process involving the admixing of an aqueous silica sol with a particle diameter of 1-150 nm and polyetherols or polyether amines, followed by distillation and surface modification with monoalkoxylated silanes, to create stable dispersions that can be used as polyol components in polyurethane production, reducing particle size and improving compatibility with polyol components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional methods using expensive precursors and large particle sizes are used, then production cost is reduced and handling is easier, but reinforcement effectiveness and nanoscale filler performance are compromised
Solution Approach 1:
The patent changes the particle size parameter from conventional large sizes to nanoscale 1-150 nm range, achieving superior reinforcement effectiveness while controlling production costs through optimized synthesis parameters and avoiding expensive precursors
Solution Approach 2:
The patent creates composite silica dispersions combining nanoscale silica particles with polyetherols or polyether amines, achieving both nanoscale reinforcement effectiveness and cost-effective production through the synergistic combination of materials
2Strength
If silica particles are reduced to nanoscale size, then reinforcement effectiveness is improved, but particle-particle interactions become too high making redispersion difficult
Solution Approach 1:
The patent uses polyetherols or polyether amines as intermediary substances that mediate between the nanoscale silica particles and the polyol component, providing steric stabilization that prevents excessive particle-particle interactions while maintaining nanoscale size for effective reinforcement
Solution Approach 2:
The patent changes the surface chemistry parameters of the silica particles through interaction with polyetherols or polyether amines, modifying surface properties to reduce particle-particle attraction while maintaining nanoscale dimensions for effective reinforcement
3Quantity of substance
If aqueous silica sol is used with high silica content, then dispersion concentration is improved, but water removal requires extensive distillation increasing production time and energy consumption
Solution Approach 1:
The patent changes the compositional parameters by using polyetherols or polyether amines with specific molecular weights and functionalities that enable direct incorporation of high silica content dispersions into polyol components, eliminating or reducing the need for extensive water removal distillation steps
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This process enables the production of stable, high-concentration silica dispersions with improved mechanical properties in polyurethane materials, enhancing their acoustic and thermal insulation capabilities without the need for expensive solvents or occupational hazards.
Implementation Method 1
admixing an aqueous silica sol (K) having an average particle diameter of from 1 to 150 nm... followed by distillation
Implementation Method 2
surface modification with monoalkoxylated silanes
Data Source
AI summary
Process for producing silica-comprising dispersions comprising a polyetherol or a polyether amine, which comprises the steps of(i) admixing an aqueous silica sol (K) having an average particle diameter of from 1 to 150 nm and a silica content, calculated as SiO2, of from 1 to 60% by weight and a pH of from 1 to 6 with at least one polyetherol (b1) and/or polyether amine (b2) based on ethylene oxide and/or propylene oxide and having an average OH or amine functionality of from 2 to 6 and a number average molecular weight of from 62 to 6000 g/mol,(ii) distilling off at least part of the water,(iii) admixing the dispersion with at least one compound (S) having at least one at least monoalkoxylated silyl group and at least one alkyl, cycloalkyl or aryl substituent, where this substituent may have groups which are reactive toward an alcohol, an amine or an isocyanate in an amount of from 0.1 to 20 μmol of (S) per m2 of surface area of (K), where steps (i) and (iii) can be carried out simultaneously or in succession in any order,(iv) optionally adjusting the pH of the silica-comprising dispersions obtained to a value of from 7 to 12 by adding a basic compound, where step (iv) can also be carried out between steps (ii) and (iii).